The overall objective of this proposal is to investigate the mechanism by which gonadotropins regulate the corpus luteum function. Attempts are in progress to investigate the role of cyclic AMP as a second messenger in transmitting the hormonal response. More specifically, the role of cyclic AMP in modifying the transcriptional and/or translational control on the synthesis of progesterone is under investigation. The cellular mechanisms being investigated include the activation of protein kinase by cAMP, the biological substrate for protein kinase in corpus luteum and the effect of cyclic AMP on nuclear metabolism.